A common technique to sterilize objects used in e.g. hospitals, laboratories and the pharmaceutical industry is to use a sterilization apparatus such as an autoclave. A sterilization apparatus typically comprises a chamber for receiving the objects to be sterilized, a fluid system for supplying a sterilization medium to the objects inside the chamber and a drain system or vent path for discharging the sterilization medium out from the chamber.
In steam sterilization, steam is introduced into the chamber and the temperature is increased to a sterilization temperature. After a predefined sterilization time, which depends on the sterilization temperature used, the steam is evacuated from the chamber through the drain system. The steam may then be condensed and discharged from the system. These above-mentioned process steps may be referred to as a process cycle or a process scheme.
The discharge of sterilization medium from the chamber to the drain system is designed to conform to the other steps in the process cycle. Therefore the discharge of sterilization medium from the chamber to the drain system is adapted to a certain sterilization chamber and a certain sterilization process cycle. However, in some cases there is a need for increasing or decreasing the discharged flow.
U.S. Pat. No. 4,781,898 discloses a sterilization pressure chamber of an autoclave with two valve controlled vent paths. A first vent path channels the sterilizing steam from the chamber into a condensing coil having an end which opens into a liquid reservoir. When the pressure within the chamber drops to a predetermined level, a second vent path, having a flow rate which is greater than the first path, opens and provides a channel for the rapid escape of the remainder of the steam from the chamber. Hence, the autoclave may be vented in a faster manner.
It would be desirable to provide a sterilization apparatus where the drain system is able to discharge the sterilization fluid from the chamber in an even faster manner.